Sugar, diabetes and why the state of our health is not about any one thing. Many of the nutrition studies we share with GI News readers are prospective studies. Looking at large groups of people over a period of time (usually many years), the researchers mine the data (rather like gold prospectors) looking for links between diet (e.g., consumption of fruit or vegetables or red meat or whole grains or sugar) and health. What you need to remember when you read (or watch) headline-hitting health stories featuring research findings from such studies is that the correlations or associations they find don’t actually establish causation. Prof David Katz comments on a recent study in Plos One using econometric models of repeated cross-sectional data of the association between sugar intake and diabetes around the world. Here is an edited summary of his Huffington Post piece reproduced with permission.

Dr. David Katz

‘The study itself, published in the journal Plos One, is excellent overall. This kind of ecological evaluation – looking at an association between X and Y at the population level is certainly of some value. But it is absolutely not the “closest thing to causation” – in fact, it is among the least reliable forms of evidence. At the population level, the presence of a Bentley in the driveway, or a high-speed Internet connection in the home, is profoundly associated with reduced likelihood of malaria (or tuberculosis, or leprosy, etc.). This is absolutely not because Bentleys or the Internet protect against leprosy or malaria. Rather, affluent people with expensive cars and high-speed Internet access are much less likely to encounter malaria or leprosy than the poor for reasons having nothing to do with horsepower, or bandwidth.

Fundamentally, Dr Basu’s team found that the greater the availability of daily calories from sugar around the world, the more diabetes. I’m having some trouble figuring out what is supposed to be surprising about this. If people add sugar calories to their diets, they are getting both more sugar, and more calories, and those exposures alone and together are well known to contribute to diabetes risk. If they are adding sugar calories in place of other calories, then the percentage of total daily calories coming from sugar is going up, and the overall quality of diet is going down. Again, this pattern is pretty well linked to diabetes risk (and other chronic disease risk, for that matter) already.

To some extent, the Basu study was a self-fulfilling prophecy. It’s true the researchers looked at other associations between diet and diabetes. But consider that one food category was “meat,” which presumably lumped together everything from salmon to salami. Some such “meats” likely defend against diabetes, while others would likely increase risk. Lumped together, nothing much would be visible. Similarly, there was a category of “cereals,” but with no distinction between whole grains and refined starch. Putting everything from steel-cut oats to Cap’n Crunch in one category would not facilitate keen insights. The authors did not look at nuts and seeds, despite numerous studies – including one just published in the Journal of Nutrition – demonstrating that higher intake of walnuts and other nuts is associated with reduced diabetes risk.

Since Dr Basu’s methods involved looking at sugar dose available in the food supply per person per day, and the prevalence of diabetes in the population, there is nothing in the data to prove that those who ate the most sugar were most likely to develop diabetes – although one may infer that. Rather, as countries make more sugar calories available each day (i.e., become more like the US), their populations have more diabetes. Again, this is not terribly surprising.

But it’s more than a little wrong to conclude that since sugar intake contributes to diabetes risk, nothing else matters. In fact, Dr Basu and colleagues state explicitly that increasing sugar availability accounts for roughly one-quarter of the global rise in diabetes rates between 2000 and 2010. This clearly implies that something other than sugar accounts for almost 75 percent of that increase.

The reality, alas, is that the state of our health is not about any one thing. We can cut fat, and get fatter and sicker – by eating more starchy, sugary junk. We can cut carbs by switching from beans to baloney, and get fatter and sicker. And we can cut sugar and consume ever more artificially-sweetened, starchy, fatty junk – and get fatter and sicker. We clearly like little bits of truth we find easy to digest. But none of these is the whole truth, and when bits of truth are mistaken for the whole – they might just as well be falsehoods.’

About Dr David KatzKnown internationally for expertise in nutrition, weight management, and chronic disease prevention, Katz is the founding director of Yale University's Prevention Research Center. He is the founder and President of the non-profit Turn the Tide Foundation, and a blogger/medical review board member for The Huffington Post. www.davidkatzmd.com

Dementia risk and BGLs.
Blood sugar levels averaged over a five-year period were associated with rising risks for developing dementia, according to the findings of a recent study published in the New England Journal of Medicine. For example:

In people without diabetes, risk for dementia was 18% higher for people with an average glucose level of 115 milligrams per deciliter (6.4 mmol/L) compared to those with an average glucose level of 100 mg/dl (5.6 mmol/L)

In people with diabetes, whose blood sugar levels are generally higher, dementia risk was 40% higher for people with an average glucose level of 190 mg/dl (10.6 mmol/L) compared to those with an average glucose level of 160 mg/dl (8.9 mmol/L).

The measurements included blood glucose (some fasting, some not) and glycated hemoglobin (also known as HbA1c).

Dr Paul Crane

‘The most interesting finding was that every incrementally higher glucose level was associated with a higher risk of dementia in people who did not have diabetes,’ said first author Dr Paul K. Crane. ‘There was no threshold value for lower glucose values where risk leveled off.’ However, he emphasized that these results come from an observational study: ‘What we found was that people with higher levels of glucose had a higher risk of dementia, on average, than did people with lower levels of glucose,’ he said. ‘While that is interesting and important, we have no data to suggest that people who make changes to lower their glucose improve their dementia risk. Those data would have to come from future studies with different study designs.’

GI News's Dr Alan Barclay stated that it is good to see Dr Crane emphasising the point that the results are from an observational study and as such do not prove causality; just an association. At this point in time, we don’t know if reducing glucose will reduce dementia risk. We need to conduct a randomised controlled trial to test that hypothesis.

Catching up on sleep. Dr Peter Liu

Men who lose sleep during the working week may be able to lower their risk of developing Type 2 diabetes by getting more hours of sleep, according to research findings presented at The Endocrine Society’s 95th Annual Meeting in San Francisco. ‘We all know we need to get adequate sleep, but that is often impossible because of work demands and busy lifestyles,’ said Dr Peter Liu an LA BioMed lead researcher. ‘Our study found extending the hours of sleep can improve the body’s use of insulin, thereby reducing the risk of type 2 diabetes in adult men.’

Liu and researchers from the University of Sydney studied 19 non-diabetic men, with an average age of 28, who for six months or longer (average, 5 years) self-reported inadequate sleep during the work week – around 6 hours a night. But they regularly caught up on their sleep on the weekends, getting at least a third more sleeping time a night. Their reported sleep times were verified by actigraphy, in which each man wore a small device on his wrist that monitored sleep-wake cycles. The men spent three nights in a sleep lab on each of two separate weekends and each individual had the same food intake during the study visits, so that diet would not influence the results. When the men slept 10 hours a night on each of three nights of catch-up sleep, their insulin sensitivity was much better than when they had persistent sleep restriction. Their insulin resistance test score also improved (decreased) with sleep extension.

Being rich or poor in gut bacteria.
A study in Nature reports that people with fewer bacterial species in their intestines may be more likely to develop cardiovascular disease and diabetes. The researchers examined the intestinal flora of 169 obese Danes and 123 non-obese Danes using an analytical approach called quantitative metagenomics. When comparing the two groups, they discovered that people with a low richness microbiota have more body fat and less healthy; they are more resistant to the action of insulin, have unfavorably altered blood lipids and show increased blood levels of inflammation markers and white blood cells, bringing them at increased risk of type 2 diabetes and cardiovascular disorders. They also observed that obese people from the low richness group gained on average significantly more weight than the high richness one during the past nine years.

The gut is like a rainforest says Oluf Pedersen. It appears that the richer and more diverse the composition of our intestinal bacteria, the stronger our health. The bacteria produce vital vitamins, mature and strengthen our immune system and communicate with the many nerve cells and hormone-producing cells in the intestinal system. And, not least, the bacteria produce a wealth of bioactive substances which penetrate into the bloodstream and affect our biology in countless ways.

Is stomach damage why diets are doomed to fail? Associate Professor Amanda Page
The way the stomach detects and tells the brain how full the body is becomes damaged in obese people, but does not return to normal once they lose weight, according to findings of a mouse study published in the International Journal of Obesity. The nerves in the stomach that signal fullness to the brain appear to be desensitised after long-term consumption of a high-fat diet. Researchers believe this could be a key reason why most people who lose weight on a diet eventually put that weight back on.

‘The stomach’s nerve response does not return to normal upon return to a normal diet,’ said Associate Professor Amanda Page from the University of Adelaide’s Nerve-Gut Research Laboratory and the study’s lead author. ‘This means you would need to eat more food before you felt the same degree of fullness as a healthy individual. In normal conditions, leptin (a hormone) acts to stop food intake. However, in the stomach in high-fat diet induced obesity, leptin further desensitises the nerves that detect fullness. These two mechanisms combined mean that obese people need to eat more to feel full, which in turn continues their cycle of obesity,’ she said.
The researchers said there were not yet sure whether the desensitisation of the stomach nerves is a permanent effect, or just a long-lasting one. ‘We know that only about 5 per cent of people on diets are able to maintain their weight loss, and that most people who’ve been on a diet put all of that weight back on within two years.’

What’s new?Disease-Proof. DNA is not destiny.

Abundant scientific evidence shows that not smoking, eating well, being active, and maintaining a healthy weight play an enormous role in our health. Drawing upon the latest scientific evidence and decades of clinical experience, Dr. Katz arms us with the skills to make lasting changes in each of these areas. Disease-Proofequips readers with the knowledge to manage weight, improve immune function, reprogram our genes, and prevent and reverse life-altering illnesses.
DNA is not destiny. To a much greater extent, choices under our control determine our fate. We have scientific evidence to show that if we change our own behavior, we change the behavior of our genes. We can nurture nature.
The relevant skills aren’t trivial, but they aren’t really hard, either. You can have them -- but you have to go get them. Remember you once had to learn how to ride a bike. But then... you’ve known how ever since. Without the right skill set, health is elusive.

Tomato magic. ‘Knowledge is knowing a tomato is a fruit. Wisdom is not putting it in fruit salad.’
This is one of my favourite quotable quotes and refers to one of the many botanical versus culinary inconsistencies in the world of food. Olives and avocadoes are the other obvious examples of fruits that we usually eat as vegetables. If you’re botanically inclined, tomatoes are a fruit because they form from the flower, and the seeds are inside. But it’s also obvious when you taste a really good one because they taste so deliciously sweet. Much like other fruits, they’re also rich in vitamin C.

‘You say to-may-to, I say to-mah-to, let’s call the whole thing off.’
The widely popular ruby fruit also features in this famous song lyric, although unlike Louie Armstrong and Ella Fitzgerald, everyone agrees tomatoes are great.
The tomato is iconic to Italian cuisine and integral to many other Mediterranean countries as well. The beautiful balance of sweetness, zingy acidity and natural saltiness makes it the perfect partner for just about everything including pasta and pizza. Can’t come at legumes? Try them in a tomato ragu and voila: totally yum. Can’t take to green beans? Cook them up in tomato passata and you’ll be converted. Turn your nose up at eggplant or zucchini (courgette)? You’ll change your tune when they make sweet music with tomato in a ratatouille (great kids movie too). And don’t fret about the cooking or processing of tomatoes because their antioxidants including the red pigment lycopene actually become more available to the body when pureed and cooked with oil; what a bonus! And this enhanced absorption also applies to tomato juice found in Bloody Marys (although Virgin Marys sans alcohol are healthier of course). You might have heard that lycopene may reduce the risk of prostate cancer in men but studies have also shown benefits for cholesterol and protecting skin against UV damage.

Most commercially produced tomatoes have compromised flavour for hardness that allows them to be transported more easily but tomatoes are fairly easy to grow yourself either in the garden or in a pot, and the itty-bitty cherry varieties are both hardy and prolific. I’d go as far as to say they’re better for flavour as well. There is now a trend toward old fashioned heirloom varieties however these are still hard to find in the shops so grow your own: once you’ve tasted a really good tomato it’s hard to go back. And for any tomato it’s always better to eat them at room temperature. For a truly gorgeous feast for the eyes as well as the mouth, simply roast a whole sprig of cherry tomatoes drizzled in olive oil and bejewel your plate with culinary treasure. If your harvest cup runneth over, preserve your delights for later by making your own passata (which can be bottled or frozen) or slow roast them and store under oil in the fridge. Slow roasted tomatoes look a shadow of their former selves but beautiful on the inside with concentrated flavour. Use them on sandwiches, wraps, pizza, salads or stirred through pasta (but ensure you enjoy some hot with a dash of balsamic vinegar).

Speaking of harvest cups running over, you will no doubt have heard of the mad Spaniards in the town of La Tomatina and their annual organised mega food-fight where they throw 90,000 pounds of squashed, inedible tomatoes at each other. Now we can add ammunition and entertainment to an already bulging list of talents for this ever-versatile fruit/vegetable. That’s what I call tomato magic.

Nicole Senior is an Accredited Practising Dietitian and Nutritionist, author, speaker, consultant, and commentator with an interest in how we can learn to love good food that's good for us.

Family Baking, Anneka Manning, author of Bake Eat Love. Learn to Bake in 3 Simple Steps and founder of Sydney’s BakeClub,
shares her delicious ‘better-for-you’ recipes for snacks, desserts and
treats the whole family will love. Through both her writing and cooking
school, Anneka teaches home cooks to bake in practical and approachable
yet inspiring ways that assure success in the kitchen.

Baked eggs in nests with tomato and spinach.
This delicious combination of egg, spinach and tomato is held within a clever individual bread basket and then baked – perfect for breakfast or a light lunch it will be popular with both kids and adults alike.
Makes: 4
Preparation time: 20 minutes
Baking time: 15-20 minutes

Preheat the oven to 180°C/350°F.Use your fingertips to flatten the bread slices slightly. Brush both sides of the slices lightly with the olive oil or spray lightly with the olive oil spray. Press each into a 3/4 cup muffin tin hole to line.Place the spinach leaves into the bread cups to line and then top each with a tablespoon of homemade tomato sauce. One-by-one break an egg into a ramekin or small dish and then slide into the bread cups. Sprinkle with the cheese, top with another tablespoonful of the sauce. Sprinkle with the parsley and season well with the pepper.Bake in preheated oven for 15 minutes for a soft yolk or 20 minutes for a hard yolk. Serve warm with extra sauce if desired.

Homemade tomato sauce.
This versatile, fresh-flavoured sauce will become a staple – perfect tossed through pasta, spread over pizzas and served as an accompaniment it is well worth making double and storing it the freezer for another time.
Makes: about 1-1/4 cups
Preparation time: 10 minutes
Cooking time: 35-40 minutes

Put the olive oil and onion in a medium saucepan over medium heat and cook, stirring occasionally, for 8 minutes or until the onion is tender.Add the garlic and oregano and cook for 1 minute or until aromatic. Add the tomatoes and bring to the boil.Reduce the heat to low and simmer for 25-30 minutes, stirring occasionally, or until thickened to a thick sauce consistency.Remove from the heat and season with sugar, salt and freshly ground black pepper, to taste. Set aside to cool. Any leftover sauce will keep in an airtight container in the fridge for up to 4 days or in the freezer for up to 3 months.

Here's how you can cut back on the food bills and enjoy fresh-tasting,
easily prepared, seasonal, satisfying and delicious low or moderate GI
meals that don’t compromise on quality and flavour one little bit with
our Money Saving Meals including this wonton soup.

Wonton soup.
Now in season in Australia, asparagus is one of the best dietary sources of inulin an indigestible part of food that enters the large bowel to become food for the healthy bacteria that happily reside there. For that reason it is called a prebiotic (a food for bacteria). This recipe is reproduced courtesy the Australian Asparagus Council www.asparagus.com.au Serves 4

Place the stock in a large saucepan and bring to the boil.
Reduce heat to a simmer and stir in the ginger, soy sauce, sugar and sesame oil.
Add the wontons into the stock and cook for 3 minutes. Add the asparagus and snow peas, and cook a further 2 minutes.Ladle the soup into serving bowls, and garnish with the chilli and herbs, then drizzle with the garlic oil.

American dietitian and author of Good Carbs, Bad Carbs, Johanna Burani, shares favourite recipes with a low or moderate GI from her Italian kitchen. For more information, check out Johanna's website. The photographs are by Sergio Burani. His food, travel and wine photography website is photosbysergio.com.

Oaty apple muffins
I’ve never found oat bran in any Italian supermarket, specialty shop or health food store. Even oats are less ubiquitous there. That’s why when I go to Italy, I fill my suitcase with boxes and bags of this wonderful grain and make these oaty muffins to share with my neighbors, friends and family. If they’re interested, I explain that the soluble fiber in the oats helps to lower cholesterol. They love the taste and I love seeing them eating something that’s good for them. In this recipe the muffin size is deliberately small because of the high fiber content. Chopped fresh fruit or nuts can be added. Makes 24

The evolution of dietary recommendations for diabetes.
They knew about diabetes in ancient Egypt. Physician Hesy-Ra of the 3rd Dynasty describes various diseases including a polyuric syndrome, presumably diabetes, in what is now known as the Ebers papyrus (1500BCE). Ancient Ayurvedic texts from India go further describing two types of diabetes-like conditions – congenital and late onset – and noting the relationship of diabetes to heredity, obesity, sedentary life and diet. Talk about the wisdom of the ancients. Today research has completely confirmed that relationship – diabetes risk comes from a combination of diet and lifestyle factors and not from any single nutrient or food (such as sugar or soft drinks) and also tends to run in families. Over the years, people with diabetes have been forced to undergo a number of very challenging dietary regimens. Here we summarise.

1797 Scottish physician John Rollo prescribes an ‘animal diet’ for his patients of ‘plain blood puddings’ and ‘fat and rancid meat’ so to manage the disease with foods their bodies could assimilate.1871 French physician Apollinaire Bouchardat notices the disappearance of glycosuria (sweet urine) in his diabetes patients during food rationing under the Siege of Paris in the Franco-Prussian War, and formulates individualised diets to treat the condition.1916 Boston pathologist Elliott Joslin compiles 1000 of his own cases and creates the textbook The Treatment of Diabetes Mellitus. In it he reports that ‘the mortality of patients was approximately 20 per cent lower than for the previous year’, due to ‘the introduction of fasting and the emphasis on regular exercise’.1919 Dr Frederick Allen of the Rockefeller Institute in New York publishes his Total Dietary Regulations in the Treatment of Diabetes that introduces a therapy of strict dieting – dubbed the ‘starvation treatment’ – as a way to manage diabetes.

1921 Insulin was discovered by Canadians Dr Frederick Banting and Charles Best and became commercially available towards the end of 1922 revolutionising the management of diabetes throughout the world. The refusal to patent insulin but to share this miraculous therapy freely with the world will remain an outstanding example of unreserved generosity towards mankind in the history of medical disease. Banting’s colossal contribution has been globally recognised by the declaration, since 2007, of his birthday (14th November) as World Diabetes Day.

1923 Dr H. Rawle Geyelin demonstrated that a higher carbohydrate diet did not upset blood glucose levels as long as enough insulin was supplied.1950 The American Diabetic Association and American Dietetic Association developed and published the first set of carbohydrate exchange lists.1970s Major diabetes organisations review their dietary recommendations due to the increasing number of deaths of people with diabetes from heart and blood vessel diseases. Recommendations for dietary fat dropped to less than 35% calories and carbohydrate recommendations went up to 55–60% of calories. Researchers found that the nutritional status of patients improved with a higher carbohydrate intake, and their insulin sensitivity improved as well.1981 Dr David Jenkins, Dr Tom Wolever and colleagues develop the concept of the glycemic index (GI) of foods and publish their findings, A physiological basis of carbohydrate exchange, in the American Journal of Clinical Nutrition1994 The American Diabetes Association completed a major revision of its dietary guidelines for people with diabetes acknowledging that there was no one right diet and dropping specific recommendations to limit the amount of simple sugars.1997 World Health Organization/Food and Agriculture Organization recommended using the GI as the best guide to the effect of carbohydrate foods on blood glucose levels.2008 A systematic reviewGlycemic index, glycemic load, and chronic disease risk–a meta-analysis of observational studies was published reporting that those eating the highest GI diet had a 40% higher risk of type 2 diabetes than those with the lowest GI diet. When it comes to diet and diabetes risk, the researchers found that the overall glycemic load of the diet (i.e. the total amount of carbohydrate x GI) is the biggest potential problem.

Dr Alan BarclayDiabetes and pre-diabetes epidemic in China.
China is now the global epicentre of diabetes and pre-diabetes according to new research in the Journal of the American Medical Association. Nearly two out of three Chinese adults has diabetes or prediabetes. In 2010, a survey of Chinese adults found that 11.6%, equivalent to a staggering 113.9 million people, had diabetes, and unfortunately only one in three were aware that they had the condition. In addition, just over half (50.1%) of all Chinese adults had prediabetes, equivalent to an even more staggering 493.4 million people.

Perhaps surprisingly, unlike other countries with similarly high diabetes prevalence rates, the average adult in China is not nearly as overweight as their Western counterparts.
It’s thought that poor nutrition during pregnancy and the early life of the child, combined with over-nutrition in later life, may be contributing to the accelerated epidemic of diabetes in China. In addition, rapid economic growth and associated industrialization, urbanization, and lifestyle changes (increased high-calorie diets high in refined carbohydrates and fats and decreased physical activity) are taking their toll.

Traditionally, Chinese people consume a high carbohydrate diet, with a very high proportion of their calories coming from white rice. While they were physically active and relatively lean, this was not a major health issue, but as they have become more sedentary, and adopted more Western foods into their diets, the high glycemic load may be contributing to the development of type 2 diabetes.

The good news is that there is strong evidence that at least 50% of people with pre-diabetes can prevent or delay its progression to type 2 diabetes through regular physical activity (at least 30 minutes a day), modest weight reduction (5-10% of initial body weight) moderate calorie restriction (eating 500 less calories a day), and eating a diet low in saturated fat (less than 10% of calories) and high in fibre (25-30 g a day).

As regular readers know, there is also very good evidence that lowering the glycemic load of the diet will also reduce the risk of type 2 diabetes. In China, there are a number of staple foods with a high glycemic load such as rice, noodles, bread, and potatoes. There are low GI versions of these foods so swapping high for healthy low GI varieties is one strategy to help reduce body weight and the associated diabetes risk. Healthy swaps include:

Isn’t the insulin response more important than the GI value? Wouldn’t it be better to have an insulin index of foods?
The insulin demand exerted by foods is indeed important for long-term health, but it doesn’t necessarily follow that we need an insulin index of foods instead of a glycemic index. When they have been tested together, the glycemic index is extremely good at predicting a food’s insulin index. (In other words, a low GI food has a low insulin index value and a high GI food has a high insulin index value.) There are some instances, however, in which a food has a low GI but a high insulin index value. This applies to dairy foods and to some highly palatable, energy-dense ‘indulgence foods’. Some foods (such as meat, fish and eggs) that contain no carbohydrate, just protein and fat (and have a GI of essentially zero), still stimulate significant increases in blood insulin. We don’t currently know how to interpret this type of response for long-term health. It may be a good outcome, because the increase in insulin has contributed to the low level of glycemia. On the other hand, it may be less than ideal, because the increased demand for insulin contributes to beta-cell ‘exhaustion’ and the development of type 2 diabetes. Until studies are carried out to answer these types of questions, the glycemic index remains a proven dietary tool for predicting the effects of food on health.

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